A typical liquid crystal display (LCD) is capable of displaying a clear and sharp image through millions of pixels that make up the complete image. The liquid crystal display has thus been applied to various electronic equipment in which messages or pictures need to be displayed, such as mobile phones and notebook computers.
In the manufacture of a typical LCD, an essential requirement is the alignment of liquid crystal molecules on a surface of an alignment layer (hereinafter “alignment surface”) of the LCD. The liquid crystal molecules are placed on the alignment surface prior to the formation of the LCD cell that contains the alignment layer and the liquid crystal molecules. The most widely used method for producing the alignment surface is to coat a film, such as a polyimide film, on a base layer such as a glass substrate. The polyimide film forms the base material of the alignment layer. The surface of the polyimide film coating is then rubbed with a velvet cloth. This rubbing process realigns the polyimide surface to form the alignment surface. The alignment surface provides a directional template for the alignment of the liquid crystal molecules in contact with the surface.
The rubbing method has been the process of choice for as much as the last three decades in order to provide alignment surfaces required for LCDs. However, the LCD industry has recognized that a non-rubbing method or a non-contact method of surface alignment would be very desirable for manufacturing in the future. This is because the rubbing process introduces debris from the cloth into an otherwise unpolluted clean room environment. The rubbing process can also lead to electrostatic charge build up, which can destroy transistors located on the glass substrate below the polyimide surface. Since these transistors are essential for the operation of modern LCDs. Therefore it is especially important that forming the alignment surface does not threaten the viability of these transistors.
What is needed, therefore, is a no-contact alignment apparatus for producing an alignment surface. What is also needed is a no-contact alignment method for producing an alignment surface.